usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver

This patch introduces the main part of Cadence USBSSP DRD driver
to Linux kernel.
To reduce the patch size a little bit, the header file gadget.h was
intentionally added as separate patch.

The Cadence USBSSP DRD Controller is a highly configurable IP Core which
can be instantiated as Dual-Role Device (DRD), Peripheral Only and
Host Only (XHCI)configurations.

The current driver has been validated with FPGA platform. We have
support for PCIe bus, which is used on FPGA prototyping.

The host side of USBSS DRD controller is compliant with XHCI.
The architecture for device side is almost the same as for host side,
and most of the XHCI specification can be used to understand how
this controller operates.

Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>

14 files changed, 6639 insertions, 29 deletions

diff --git a/drivers/usb/cdns3/Kconfig b/drivers/usb/cdns3/Kconfig
index 58154c0a73ac..b98ca0a1352a 100644
--- a/drivers/usb/cdns3/Kconfig
+++ b/drivers/usb/cdns3/Kconfig
@@ -1,21 +1,28 @@
-config CDNS_USB_COMMON
-	tristate
+config USB_CDNS_SUPPORT
+	tristate "Cadence USB Support"
+	depends on USB_SUPPORT && (USB || USB_GADGET) && HAS_DMA
+	select USB_XHCI_PLATFORM if USB_XHCI_HCD
+	select USB_ROLE_SWITCH
+	help
+	  Say Y here if your system has a Cadence USBSS or USBSSP
+	  dual-role controller.
+	  It supports: dual-role switch, Host-only, and Peripheral-only.
 
-config CDNS_USB_HOST
+config USB_CDNS_HOST
 	bool
 
+if USB_CDNS_SUPPORT
+
 config USB_CDNS3
 	tristate "Cadence USB3 Dual-Role Controller"
-	depends on USB_SUPPORT && (USB || USB_GADGET) && HAS_DMA
-	select USB_XHCI_PLATFORM if USB_XHCI_HCD
-	select USB_ROLE_SWITCH
-	select CDNS_USB_COMMON
+	depends on USB_CDNS_SUPPORT
 	help
 	  Say Y here if your system has a Cadence USB3 dual-role controller.
 	  It supports: dual-role switch, Host-only, and Peripheral-only.
 
 	  If you choose to build this driver is a dynamically linked
 	  as module, the module will be called cdns3.ko.
+endif
 
 if USB_CDNS3
 
@@ -32,7 +39,7 @@ config USB_CDNS3_GADGET
 config USB_CDNS3_HOST
 	bool "Cadence USB3 host controller"
 	depends on USB=y || USB=USB_CDNS3
-	select CDNS_USB_HOST
+	select USB_CDNS_HOST
 	help
 	  Say Y here to enable host controller functionality of the
 	  Cadence driver.
@@ -72,3 +79,44 @@ config USB_CDNS3_IMX
 	  For example, imx8qm and imx8qxp.
 
 endif
+
+if USB_CDNS_SUPPORT
+
+config USB_CDNSP_PCI
+	tristate "Cadence CDNSP Dual-Role Controller"
+	depends on USB_CDNS_SUPPORT && USB_PCI && ACPI
+	help
+	  Say Y here if your system has a Cadence CDNSP dual-role controller.
+	  It supports: dual-role switch Host-only, and Peripheral-only.
+
+	  If you choose to build this driver is a dynamically linked
+	  module, the module will be called cdnsp.ko.
+endif
+
+if USB_CDNSP_PCI
+
+config USB_CDNSP_GADGET
+	bool "Cadence CDNSP device controller"
+	depends on USB_GADGET=y || USB_GADGET=USB_CDNSP_PCI
+	help
+	  Say Y here to enable device controller functionality of the
+	  Cadence CDNSP-DEV driver.
+
+	  Cadence CDNSP Device Controller in device mode is
+	  very similar to XHCI controller. Therefore some algorithms
+	  used has been taken from host driver.
+	  This controller supports FF, HS, SS and SSP mode.
+	  It doesn't support LS.
+
+config USB_CDNSP_HOST
+	bool "Cadence CDNSP host controller"
+	depends on USB=y || USB=USB_CDNSP_PCI
+	select USB_CDNS_HOST
+	help
+	  Say Y here to enable host controller functionality of the
+	  Cadence driver.
+
+	  Host controller is compliant with XHCI so it uses
+	  standard XHCI driver.
+
+endif
diff --git a/drivers/usb/cdns3/Makefile b/drivers/usb/cdns3/Makefile
index 16df87abf3cf..a84b129f14b8 100644
--- a/drivers/usb/cdns3/Makefile
+++ b/drivers/usb/cdns3/Makefile
@@ -1,20 +1,25 @@
 # SPDX-License-Identifier: GPL-2.0
 # define_trace.h needs to know how to find our header
-CFLAGS_trace.o				:= -I$(src)
+CFLAGS_trace.o					:= -I$(src)
 
-cdns-usb-common-y			:= core.o drd.o
-cdns3-y					:= cdns3-plat.o
+cdns-usb-common-y				:= core.o drd.o
+cdns3-y						:= cdns3-plat.o
 
-obj-$(CONFIG_USB_CDNS3)			+= cdns3.o
-obj-$(CONFIG_CDNS_USB_COMMON)		+= cdns-usb-common.o
+obj-$(CONFIG_USB_CDNS3)				+= cdns3.o
+obj-$(CONFIG_USB_CDNS_SUPPORT)			+= cdns-usb-common.o
 
-cdns-usb-common-$(CONFIG_CDNS_USB_HOST) += host.o
-cdns3-$(CONFIG_USB_CDNS3_GADGET)	+= gadget.o ep0.o
+cdns-usb-common-$(CONFIG_USB_CDNS_HOST) 	+= host.o
+cdns3-$(CONFIG_USB_CDNS3_GADGET)		+= gadget.o ep0.o
 
 ifneq ($(CONFIG_USB_CDNS3_GADGET),)
-cdns3-$(CONFIG_TRACING)			+= trace.o
+cdns3-$(CONFIG_TRACING)				+= trace.o
 endif
 
-obj-$(CONFIG_USB_CDNS3_PCI_WRAP)	+= cdns3-pci-wrap.o
-obj-$(CONFIG_USB_CDNS3_TI)		+= cdns3-ti.o
-obj-$(CONFIG_USB_CDNS3_IMX)		+= cdns3-imx.o
+obj-$(CONFIG_USB_CDNS3_PCI_WRAP)		+= cdns3-pci-wrap.o
+obj-$(CONFIG_USB_CDNS3_TI)			+= cdns3-ti.o
+obj-$(CONFIG_USB_CDNS3_IMX)			+= cdns3-imx.o
+
+cdnsp-udc-pci-y					:= cdnsp-pci.o
+obj-$(CONFIG_USB_CDNSP_PCI) 			+= cdnsp-udc-pci.o
+cdnsp-udc-pci-$(CONFIG_USB_CDNSP_GADGET)	+= cdnsp-ring.o cdnsp-gadget.o \
+						   cdnsp-mem.o cdnsp-ep0.o
diff --git a/drivers/usb/cdns3/cdnsp-ep0.c b/drivers/usb/cdns3/cdnsp-ep0.c
new file mode 100644
index 000000000000..aa220d06d887
--- /dev/null
+++ b/drivers/usb/cdns3/cdnsp-ep0.c
@@ -0,0 +1,477 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence CDNSP DRD Driver.
+ *
+ * Copyright (C) 2020 Cadence.
+ *
+ * Author: Pawel Laszczak <pawell@cadence.com>
+ *
+ */
+
+#include <linux/usb/composite.h>
+#include <linux/usb/gadget.h>
+#include <linux/list.h>
+
+#include "cdnsp-gadget.h"
+
+static void cdnsp_ep0_stall(struct cdnsp_device *pdev)
+{
+	struct cdnsp_request *preq;
+	struct cdnsp_ep *pep;
+
+	pep = &pdev->eps[0];
+	preq = next_request(&pep->pending_list);
+
+	if (pdev->three_stage_setup) {
+		cdnsp_halt_endpoint(pdev, pep, true);
+
+		if (preq)
+			cdnsp_gadget_giveback(pep, preq, -ECONNRESET);
+	} else {
+		pep->ep_state |= EP0_HALTED_STATUS;
+
+		if (preq)
+			list_del(&preq->list);
+
+		cdnsp_status_stage(pdev);
+	}
+}
+
+static int cdnsp_ep0_delegate_req(struct cdnsp_device *pdev,
+				  struct usb_ctrlrequest *ctrl)
+{
+	int ret;
+
+	spin_unlock(&pdev->lock);
+	ret = pdev->gadget_driver->setup(&pdev->gadget, ctrl);
+	spin_lock(&pdev->lock);
+
+	return ret;
+}
+
+static int cdnsp_ep0_set_config(struct cdnsp_device *pdev,
+				struct usb_ctrlrequest *ctrl)
+{
+	enum usb_device_state state = pdev->gadget.state;
+	u32 cfg;
+	int ret;
+
+	cfg = le16_to_cpu(ctrl->wValue);
+
+	switch (state) {
+	case USB_STATE_ADDRESS:
+		break;
+	case USB_STATE_CONFIGURED:
+		break;
+	default:
+		dev_err(pdev->dev, "Set Configuration - bad device state\n");
+		return -EINVAL;
+	}
+
+	ret = cdnsp_ep0_delegate_req(pdev, ctrl);
+	if (ret)
+		return ret;
+
+	if (!cfg)
+		usb_gadget_set_state(&pdev->gadget, USB_STATE_ADDRESS);
+
+	return 0;
+}
+
+static int cdnsp_ep0_set_address(struct cdnsp_device *pdev,
+				 struct usb_ctrlrequest *ctrl)
+{
+	enum usb_device_state state = pdev->gadget.state;
+	struct cdnsp_slot_ctx *slot_ctx;
+	unsigned int slot_state;
+	int ret;
+	u32 addr;
+
+	addr = le16_to_cpu(ctrl->wValue);
+
+	if (addr > 127) {
+		dev_err(pdev->dev, "Invalid device address %d\n", addr);
+		return -EINVAL;
+	}
+
+	slot_ctx = cdnsp_get_slot_ctx(&pdev->out_ctx);
+
+	if (state == USB_STATE_CONFIGURED) {
+		dev_err(pdev->dev, "Can't Set Address from Configured State\n");
+		return -EINVAL;
+	}
+
+	pdev->device_address = le16_to_cpu(ctrl->wValue);
+
+	slot_ctx = cdnsp_get_slot_ctx(&pdev->out_ctx);
+	slot_state = GET_SLOT_STATE(le32_to_cpu(slot_ctx->dev_state));
+	if (slot_state == SLOT_STATE_ADDRESSED)
+		cdnsp_reset_device(pdev);
+
+	/*set device address*/
+	ret = cdnsp_setup_device(pdev, SETUP_CONTEXT_ADDRESS);
+	if (ret)
+		return ret;
+
+	if (addr)
+		usb_gadget_set_state(&pdev->gadget, USB_STATE_ADDRESS);
+	else
+		usb_gadget_set_state(&pdev->gadget, USB_STATE_DEFAULT);
+
+	return 0;
+}
+
+int cdnsp_status_stage(struct cdnsp_device *pdev)
+{
+	pdev->ep0_stage = CDNSP_STATUS_STAGE;
+	pdev->ep0_preq.request.length = 0;
+
+	return cdnsp_ep_enqueue(pdev->ep0_preq.pep, &pdev->ep0_preq);
+}
+
+static int cdnsp_w_index_to_ep_index(__le32  wIndex)
+{
+	wIndex = le32_to_cpu(wIndex);
+
+	if (!(wIndex & USB_ENDPOINT_NUMBER_MASK))
+		return 0;
+
+	return ((wIndex & USB_ENDPOINT_NUMBER_MASK) * 2) +
+		(wIndex & USB_ENDPOINT_DIR_MASK ? 1 : 0) - 1;
+}
+
+static int cdnsp_ep0_handle_status(struct cdnsp_device *pdev,
+				   struct usb_ctrlrequest *ctrl)
+{
+	struct cdnsp_ep *pep;
+	__le16 *response;
+	int ep_sts = 0;
+	u16 status = 0;
+	u32 recipient;
+
+	recipient = ctrl->bRequestType & USB_RECIP_MASK;
+
+	switch (recipient) {
+	case USB_RECIP_DEVICE:
+		status = pdev->gadget.is_selfpowered;
+		status |= pdev->may_wakeup << USB_DEVICE_REMOTE_WAKEUP;
+
+		if (pdev->gadget.speed >= USB_SPEED_SUPER) {
+			status |= pdev->u1_allowed << USB_DEV_STAT_U1_ENABLED;
+			status |= pdev->u2_allowed << USB_DEV_STAT_U2_ENABLED;
+		}
+		break;
+	case USB_RECIP_INTERFACE:
+		/*
+		 * Function Remote Wake Capable	D0
+		 * Function Remote Wakeup	D1
+		 */
+		return cdnsp_ep0_delegate_req(pdev, ctrl);
+	case USB_RECIP_ENDPOINT:
+		pep = &pdev->eps[cdnsp_w_index_to_ep_index(ctrl->wIndex)];
+		ep_sts = GET_EP_CTX_STATE(pep->out_ctx);
+
+		/* check if endpoint is stalled */
+		if (ep_sts == EP_STATE_HALTED)
+			status =  BIT(USB_ENDPOINT_HALT);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	response = (__le16 *)pdev->setup_buf;
+	*response = cpu_to_le16(status);
+
+	pdev->ep0_preq.request.length = sizeof(*response);
+	pdev->ep0_preq.request.buf = pdev->setup_buf;
+
+	return cdnsp_ep_enqueue(pdev->ep0_preq.pep, &pdev->ep0_preq);
+}
+
+static void cdnsp_enter_test_mode(struct cdnsp_device *pdev)
+{
+	u32 temp;
+
+	temp = readl(&pdev->active_port->regs->portpmsc) & ~GENMASK(31, 28);
+	temp |= PORT_TEST_MODE(pdev->test_mode);
+	writel(temp, &pdev->active_port->regs->portpmsc);
+}
+
+static int cdnsp_ep0_handle_feature_device(struct cdnsp_device *pdev,
+					   struct usb_ctrlrequest *ctrl,
+					   int set)
+{
+	enum usb_device_state state;
+	enum usb_device_speed speed;
+	u16 tmode;
+
+	state = pdev->gadget.state;
+	speed = pdev->gadget.speed;
+
+	switch (le16_to_cpu(ctrl->wValue)) {
+	case USB_DEVICE_REMOTE_WAKEUP:
+		pdev->may_wakeup = !!set;
+		break;
+	case USB_DEVICE_U1_ENABLE:
+		if (state != USB_STATE_CONFIGURED || speed < USB_SPEED_SUPER)
+			return -EINVAL;
+
+		pdev->u1_allowed = !!set;
+		break;
+	case USB_DEVICE_U2_ENABLE:
+		if (state != USB_STATE_CONFIGURED || speed < USB_SPEED_SUPER)
+			return -EINVAL;
+
+		pdev->u2_allowed = !!set;
+		break;
+	case USB_DEVICE_LTM_ENABLE:
+		return -EINVAL;
+	case USB_DEVICE_TEST_MODE:
+		if (state != USB_STATE_CONFIGURED || speed > USB_SPEED_HIGH)
+			return -EINVAL;
+
+		tmode = le16_to_cpu(ctrl->wIndex);
+
+		if (!set || (tmode & 0xff) != 0)
+			return -EINVAL;
+
+		tmode = tmode >> 8;
+
+		if (tmode > USB_TEST_FORCE_ENABLE || tmode < USB_TEST_J)
+			return -EINVAL;
+
+		pdev->test_mode = tmode;
+
+		/*
+		 * Test mode must be set before Status Stage but controller
+		 * will start testing sequence after Status Stage.
+		 */
+		cdnsp_enter_test_mode(pdev);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int cdnsp_ep0_handle_feature_intf(struct cdnsp_device *pdev,
+					 struct usb_ctrlrequest *ctrl,
+					 int set)
+{
+	u16 wValue, wIndex;
+	int ret;
+
+	wValue = le16_to_cpu(ctrl->wValue);
+	wIndex = le16_to_cpu(ctrl->wIndex);
+
+	switch (wValue) {
+	case USB_INTRF_FUNC_SUSPEND:
+		ret = cdnsp_ep0_delegate_req(pdev, ctrl);
+		if (ret)
+			return ret;
+
+		/*
+		 * Remote wakeup is enabled when any function within a device
+		 * is enabled for function remote wakeup.
+		 */
+		if (wIndex & USB_INTRF_FUNC_SUSPEND_RW)
+			pdev->may_wakeup++;
+		else
+			if (pdev->may_wakeup > 0)
+				pdev->may_wakeup--;
+
+		return 0;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int cdnsp_ep0_handle_feature_endpoint(struct cdnsp_device *pdev,
+					     struct usb_ctrlrequest *ctrl,
+					     int set)
+{
+	struct cdnsp_ep *pep;
+	u32 wValue;
+
+	wValue = le16_to_cpu(ctrl->wValue);
+	pep = &pdev->eps[cdnsp_w_index_to_ep_index(ctrl->wIndex)];
+
+	switch (wValue) {
+	case USB_ENDPOINT_HALT:
+		if (!set && (pep->ep_state & EP_WEDGE)) {
+			/* Resets Sequence Number */
+			cdnsp_halt_endpoint(pdev, pep, 0);
+			cdnsp_halt_endpoint(pdev, pep, 1);
+			break;
+		}
+
+		return cdnsp_halt_endpoint(pdev, pep, set);
+	default:
+		dev_warn(pdev->dev, "WARN Incorrect wValue %04x\n", wValue);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int cdnsp_ep0_handle_feature(struct cdnsp_device *pdev,
+				    struct usb_ctrlrequest *ctrl,
+				    int set)
+{
+	switch (ctrl->bRequestType & USB_RECIP_MASK) {
+	case USB_RECIP_DEVICE:
+		return cdnsp_ep0_handle_feature_device(pdev, ctrl, set);
+	case USB_RECIP_INTERFACE:
+		return cdnsp_ep0_handle_feature_intf(pdev, ctrl, set);
+	case USB_RECIP_ENDPOINT:
+		return cdnsp_ep0_handle_feature_endpoint(pdev, ctrl, set);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int cdnsp_ep0_set_sel(struct cdnsp_device *pdev,
+			     struct usb_ctrlrequest *ctrl)
+{
+	enum usb_device_state state = pdev->gadget.state;
+	u16 wLength;
+
+	if (state == USB_STATE_DEFAULT)
+		return -EINVAL;
+
+	wLength = le16_to_cpu(ctrl->wLength);
+
+	if (wLength != 6) {
+		dev_err(pdev->dev, "Set SEL should be 6 bytes, got %d\n",
+			wLength);
+		return -EINVAL;
+	}
+
+	/*
+	 * To handle Set SEL we need to receive 6 bytes from Host. So let's
+	 * queue a usb_request for 6 bytes.
+	 */
+	pdev->ep0_preq.request.length = 6;
+	pdev->ep0_preq.request.buf = pdev->setup_buf;
+
+	return cdnsp_ep_enqueue(pdev->ep0_preq.pep, &pdev->ep0_preq);
+}
+
+static int cdnsp_ep0_set_isoch_delay(struct cdnsp_device *pdev,
+				     struct usb_ctrlrequest *ctrl)
+{
+	if (le16_to_cpu(ctrl->wIndex) || le16_to_cpu(ctrl->wLength))
+		return -EINVAL;
+
+	pdev->gadget.isoch_delay = le16_to_cpu(ctrl->wValue);
+
+	return 0;
+}
+
+static int cdnsp_ep0_std_request(struct cdnsp_device *pdev,
+				 struct usb_ctrlrequest *ctrl)
+{
+	int ret;
+
+	switch (ctrl->bRequest) {
+	case USB_REQ_GET_STATUS:
+		ret = cdnsp_ep0_handle_status(pdev, ctrl);
+		break;
+	case USB_REQ_CLEAR_FEATURE:
+		ret = cdnsp_ep0_handle_feature(pdev, ctrl, 0);
+		break;
+	case USB_REQ_SET_FEATURE:
+		ret = cdnsp_ep0_handle_feature(pdev, ctrl, 1);
+		break;
+	case USB_REQ_SET_ADDRESS:
+		ret = cdnsp_ep0_set_address(pdev, ctrl);
+		break;
+	case USB_REQ_SET_CONFIGURATION:
+		ret = cdnsp_ep0_set_config(pdev, ctrl);
+		break;
+	case USB_REQ_SET_SEL:
+		ret = cdnsp_ep0_set_sel(pdev, ctrl);
+		break;
+	case USB_REQ_SET_ISOCH_DELAY:
+		ret = cdnsp_ep0_set_isoch_delay(pdev, ctrl);
+		break;
+	case USB_REQ_SET_INTERFACE:
+		/*
+		 * Add request into pending list to block sending status stage
+		 * by libcomposite.
+		 */
+		list_add_tail(&pdev->ep0_preq.list,
+			      &pdev->ep0_preq.pep->pending_list);
+
+		ret = cdnsp_ep0_delegate_req(pdev, ctrl);
+		if (ret == -EBUSY)
+			ret = 0;
+
+		list_del(&pdev->ep0_preq.list);
+		break;
+	default:
+		ret = cdnsp_ep0_delegate_req(pdev, ctrl);
+		break;
+	}
+
+	return ret;
+}
+
+void cdnsp_setup_analyze(struct cdnsp_device *pdev)
+{
+	struct usb_ctrlrequest *ctrl = &pdev->setup;
+	int ret = 0;
+	__le16 len;
+
+	if (!pdev->gadget_driver)
+		goto out;
+
+	if (pdev->gadget.state == USB_STATE_NOTATTACHED) {
+		dev_err(pdev->dev, "ERR: Setup detected in unattached state\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* Restore the ep0 to Stopped/Running state. */
+	if (pdev->eps[0].ep_state & EP_HALTED)
+		cdnsp_halt_endpoint(pdev, &pdev->eps[0], 0);
+
+	/*
+	 * Finishing previous SETUP transfer by removing request from
+	 * list and informing upper layer
+	 */
+	if (!list_empty(&pdev->eps[0].pending_list)) {
+		struct cdnsp_request	*req;
+
+		req = next_request(&pdev->eps[0].pending_list);
+		cdnsp_ep_dequeue(&pdev->eps[0], req);
+	}
+
+	len = le16_to_cpu(ctrl->wLength);
+	if (!len) {
+		pdev->three_stage_setup = false;
+		pdev->ep0_expect_in = false;
+	} else {
+		pdev->three_stage_setup = true;
+		pdev->ep0_expect_in = !!(ctrl->bRequestType & USB_DIR_IN);
+	}
+
+	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
+		ret = cdnsp_ep0_std_request(pdev, ctrl);
+	else
+		ret = cdnsp_ep0_delegate_req(pdev, ctrl);
+
+	if (!len)
+		pdev->ep0_stage = CDNSP_STATUS_STAGE;
+
+	if (ret == USB_GADGET_DELAYED_STATUS)
+		return;
+out:
+	if (ret < 0)
+		cdnsp_ep0_stall(pdev);
+	else if (pdev->ep0_stage == CDNSP_STATUS_STAGE)
+		cdnsp_status_stage(pdev);
+}
diff --git a/drivers/usb/cdns3/cdnsp-gadget.c b/drivers/usb/cdns3/cdnsp-gadget.c
new file mode 100644
index 000000000000..18bb4c0d1e08
--- /dev/null
+++ b/drivers/usb/cdns3/cdnsp-gadget.c
@@ -0,0 +1,1954 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence CDNSP DRD Driver.
+ *
+ * Copyright (C) 2020 Cadence.
+ *
+ * Author: Pawel Laszczak <pawell@cadence.com>
+ *
+ */
+
+#include <linux/moduleparam.h>
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <linux/iopoll.h>
+#include <linux/delay.h>
+#include <linux/log2.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/irq.h>
+#include <linux/dmi.h>
+
+#include "core.h"
+#include "gadget-export.h"
+#include "drd.h"
+#include "cdnsp-gadget.h"
+
+unsigned int cdnsp_port_speed(unsigned int port_status)
+{
+	/*Detect gadget speed based on PORTSC register*/
+	if (DEV_SUPERSPEEDPLUS(port_status))
+		return USB_SPEED_SUPER_PLUS;
+	else if (DEV_SUPERSPEED(port_status))
+		return USB_SPEED_SUPER;
+	else if (DEV_HIGHSPEED(port_status))
+		return USB_SPEED_HIGH;
+	else if (DEV_FULLSPEED(port_status))
+		return USB_SPEED_FULL;
+
+	/* If device is detached then speed will be USB_SPEED_UNKNOWN.*/
+	return USB_SPEED_UNKNOWN;
+}
+
+/*
+ * Given a port state, this function returns a value that would result in the
+ * port being in the same state, if the value was written to the port status
+ * control register.
+ * Save Read Only (RO) bits and save read/write bits where
+ * writing a 0 clears the bit and writing a 1 sets the bit (RWS).
+ * For all other types (RW1S, RW1CS, RW, and RZ), writing a '0' has no effect.
+ */
+u32 cdnsp_port_state_to_neutral(u32 state)
+{
+	/* Save read-only status and port state. */
+	return (state & CDNSP_PORT_RO) | (state & CDNSP_PORT_RWS);
+}
+
+/**
+ * Find the offset of the extended capabilities with capability ID id.
+ * @base: PCI MMIO registers base address.
+ * @start: Address at which to start looking, (0 or HCC_PARAMS to start at
+ *         beginning of list)
+ * @id: Extended capability ID to search for.
+ *
+ * Returns the offset of the next matching extended capability structure.
+ * Some capabilities can occur several times,
+ * e.g., the EXT_CAPS_PROTOCOL, and this provides a way to find them all.
+ */
+int cdnsp_find_next_ext_cap(void __iomem *base, u32 start, int id)
+{
+	u32 offset = start;
+	u32 next;
+	u32 val;
+
+	if (!start || start == HCC_PARAMS_OFFSET) {
+		val = readl(base + HCC_PARAMS_OFFSET);
+		if (val == ~0)
+			return 0;
+
+		offset = HCC_EXT_CAPS(val) << 2;
+		if (!offset)
+			return 0;
+	};
+
+	do {
+		val = readl(base + offset);
+		if (val == ~0)
+			return 0;
+
+		if (EXT_CAPS_ID(val) == id && offset != start)
+			return offset;
+
+		next = EXT_CAPS_NEXT(val);
+		offset += next << 2;
+	} while (next);
+
+	return 0;
+}
+
+void cdnsp_set_link_state(struct cdnsp_device *pdev,
+			  __le32 __iomem *port_regs,
+			  u32 link_state)
+{
+	u32 temp;
+
+	temp = readl(port_regs);
+	temp = cdnsp_port_state_to_neutral(temp);
+	temp |= PORT_WKCONN_E | PORT_WKDISC_E;
+	writel(temp, port_regs);
+
+	temp &= ~PORT_PLS_MASK;
+	temp |= PORT_LINK_STROBE | link_state;
+
+	writel(temp, port_regs);
+}
+
+static void cdnsp_disable_port(struct cdnsp_device *pdev,
+			       __le32 __iomem *port_regs)
+{
+	u32 temp = cdnsp_port_state_to_neutral(readl(port_regs));
+
+	writel(temp | PORT_PED, port_regs);
+}
+
+static void cdnsp_clear_port_change_bit(struct cdnsp_device *pdev,
+					__le32 __iomem *port_regs)
+{
+	u32 portsc = readl(port_regs);
+
+	writel(cdnsp_port_state_to_neutral(portsc) |
+	       (portsc & PORT_CHANGE_BITS), port_regs);
+}
+
+static void cdnsp_set_chicken_bits_2(struct cdnsp_device *pdev, u32 bit)
+{
+	__le32 __iomem *reg;
+	void __iomem *base;
+	u32 offset = 0;
+
+	base = &pdev->cap_regs->hc_capbase;
+	offset = cdnsp_find_next_ext_cap(base, offset, D_XEC_PRE_REGS_CAP);
+	reg = base + offset + REG_CHICKEN_BITS_2_OFFSET;
+
+	bit = readl(reg) | bit;
+	writel(bit, reg);
+}
+
+static void cdnsp_clear_chicken_bits_2(struct cdnsp_device *pdev, u32 bit)
+{
+	__le32 __iomem *reg;
+	void __iomem *base;
+	u32 offset = 0;
+
+	base = &pdev->cap_regs->hc_capbase;
+	offset = cdnsp_find_next_ext_cap(base, offset, D_XEC_PRE_REGS_CAP);
+	reg = base + offset + REG_CHICKEN_BITS_2_OFFSET;
+
+	bit = readl(reg) & ~bit;
+	writel(bit, reg);
+}
+
+/*
+ * Disable interrupts and begin the controller halting process.
+ */
+static void cdnsp_quiesce(struct cdnsp_device *pdev)
+{
+	u32 halted;
+	u32 mask;
+	u32 cmd;
+
+	mask = ~(u32)(CDNSP_IRQS);
+
+	halted = readl(&pdev->op_regs->status) & STS_HALT;
+	if (!halted)
+		mask &= ~(CMD_R_S | CMD_DEVEN);
+
+	cmd = readl(&pdev->op_regs->command);
+	cmd &= mask;
+	writel(cmd, &pdev->op_regs->command);
+}
+
+/*
+ * Force controller into halt state.
+ *
+ * Disable any IRQs and clear the run/stop bit.
+ * Controller will complete any current and actively pipelined transactions, and
+ * should halt within 16 ms of the run/stop bit being cleared.
+ * Read controller Halted bit in the status register to see when the
+ * controller is finished.
+ */
+int cdnsp_halt(struct cdnsp_device *pdev)
+{
+	int ret;
+	u32 val;
+
+	cdnsp_quiesce(pdev);
+
+	ret = readl_poll_timeout_atomic(&pdev->op_regs->status, val,
+					val & STS_HALT, 1,
+					CDNSP_MAX_HALT_USEC);
+	if (ret) {
+		dev_err(pdev->dev, "ERROR: Device halt failed\n");
+		return ret;
+	}
+
+	pdev->cdnsp_state |= CDNSP_STATE_HALTED;
+
+	return 0;
+}
+
+/*
+ * device controller died, register read returns 0xffffffff, or command never
+ * ends.
+ */
+void cdnsp_died(struct cdnsp_device *pdev)
+{
+	dev_err(pdev->dev, "ERROR: CDNSP controller not responding\n");
+	pdev->cdnsp_state |= CDNSP_STATE_DYING;
+	cdnsp_halt(pdev);
+}
+
+/*
+ * Set the run bit and wait for the device to be running.
+ */
+static int cdnsp_start(struct cdnsp_device *pdev)
+{
+	u32 temp;
+	int ret;
+
+	temp = readl(&pdev->op_regs->command);
+	temp |= (CMD_R_S | CMD_DEVEN);
+	writel(temp, &pdev->op_regs->command);
+
+	pdev->cdnsp_state = 0;
+
+	/*
+	 * Wait for the STS_HALT Status bit to be 0 to indicate the device is
+	 * running.
+	 */
+	ret = readl_poll_timeout_atomic(&pdev->op_regs->status, temp,
+					!(temp & STS_HALT), 1,
+					CDNSP_MAX_HALT_USEC);
+	if (ret) {
+		pdev->cdnsp_state = CDNSP_STATE_DYING;
+		dev_err(pdev->dev, "ERROR: Controller run failed\n");
+	}
+
+	return ret;
+}
+
+/*
+ * Reset a halted controller.
+ *
+ * This resets pipelines, timers, counters, state machines, etc.
+ * Transactions will be terminated immediately, and operational registers
+ * will be set to their defaults.
+ */
+int cdnsp_reset(struct cdnsp_device *pdev)
+{
+	u32 command;
+	u32 temp;
+	int ret;
+
+	temp = readl(&pdev->op_regs->status);
+
+	if (temp == ~(u32)0) {
+		dev_err(pdev->dev, "Device not accessible, reset failed.\n");
+		return -ENODEV;
+	}
+
+	if ((temp & STS_HALT) == 0) {
+		dev_err(pdev->dev, "Controller not halted, aborting reset.\n");
+		return -EINVAL;
+	}
+
+	command = readl(&pdev->op_regs->command);
+	command |= CMD_RESET;
+	writel(command, &pdev->op_regs->command);
+
+	ret = readl_poll_timeout_atomic(&pdev->op_regs->command, temp,
+					!(temp & CMD_RESET), 1,
+					10 * 1000);
+	if (ret) {
+		dev_err(pdev->dev, "ERROR: Controller reset failed\n");
+		return ret;
+	}
+
+	/*
+	 * CDNSP cannot write any doorbells or operational registers other
+	 * than status until the "Controller Not Ready" flag is cleared.
+	 */
+	ret = readl_poll_timeout_atomic(&pdev->op_regs->status, temp,
+					!(temp & STS_CNR), 1,
+					10 * 1000);
+
+	if (ret) {
+		dev_err(pdev->dev, "ERROR: Controller not ready to work\n");
+		return ret;
+	}
+
+	dev_dbg(pdev->dev, "Controller ready to work");
+
+	return ret;
+}
+
+/*
+ * cdnsp_get_endpoint_index - Find the index for an endpoint given its
+ * descriptor.Use the return value to right shift 1 for the bitmask.
+ *
+ * Index = (epnum * 2) + direction - 1,
+ * where direction = 0 for OUT, 1 for IN.
+ * For control endpoints, the IN index is used (OUT index is unused), so
+ * index = (epnum * 2) + direction - 1 = (epnum * 2) + 1 - 1 = (epnum * 2)
+ */
+static unsigned int
+	cdnsp_get_endpoint_index(const struct usb_endpoint_descriptor *desc)
+{
+	unsigned int index = (unsigned int)usb_endpoint_num(desc);
+
+	if (usb_endpoint_xfer_control(desc))
+		return index * 2;
+
+	return (index * 2) + (usb_endpoint_dir_in(desc) ? 1 : 0) - 1;
+}
+
+/*
+ * Find the flag for this endpoint (for use in the control context). Use the
+ * endpoint index to create a bitmask. The slot context is bit 0, endpoint 0 is
+ * bit 1, etc.
+ */
+static unsigned int
+	cdnsp_get_endpoint_flag(const struct usb_endpoint_descriptor *desc)
+{
+	return 1 << (cdnsp_get_endpoint_index(desc) + 1);
+}
+
+int cdnsp_ep_enqueue(struct cdnsp_ep *pep, struct cdnsp_request *preq)
+{
+	struct cdnsp_device *pdev = pep->pdev;
+	struct usb_request *request;
+	int ret;
+
+	if (preq->epnum == 0 && !list_empty(&pep->pending_list))
+		return -EBUSY;
+
+	request = &preq->request;
+	request->actual = 0;
+	request->status = -EINPROGRESS;
+	preq->direction = pep->direction;
+	preq->epnum = pep->number;
+	preq->td.drbl = 0;
+
+	ret = usb_gadget_map_request_by_dev(pdev->dev, request, pep->direction);
+	if (ret)
+		return ret;
+
+	list_add_tail(&preq->list, &pep->pending_list);
+
+	switch (usb_endpoint_type(pep->endpoint.desc)) {
+	case USB_ENDPOINT_XFER_CONTROL:
+		ret = cdnsp_queue_ctrl_tx(pdev, preq);
+		break;
+	case USB_ENDPOINT_XFER_BULK:
+	case USB_ENDPOINT_XFER_INT:
+		ret = cdnsp_queue_bulk_tx(pdev, preq);
+		break;
+	case USB_ENDPOINT_XFER_ISOC:
+		ret = cdnsp_queue_isoc_tx_prepare(pdev, preq);
+	}
+
+	if (ret)
+		goto unmap;
+
+	return 0;
+
+unmap:
+	usb_gadget_unmap_request_by_dev(pdev->dev, &preq->request,
+					pep->direction);
+	list_del(&preq->list);
+
+	return ret;
+}
+
+/*
+ * Remove the request's TD from the endpoint ring. This may cause the
+ * controller to stop USB transfers, potentially stopping in the middle of a
+ * TRB buffer. The controller should pick up where it left off in the TD,
+ * unless a Set Transfer Ring Dequeue Pointer is issued.
+ *
+ * The TRBs that make up the buffers for the canceled request will be "removed"
+ * from the ring. Since the ring is a contiguous structure, they can't be
+ * physically removed. Instead, there are two options:
+ *
+ *  1) If the controller is in the middle of processing the request to be
+ *     canceled, we simply move the ring's dequeue pointer past those TRBs
+ *     using the Set Transfer Ring Dequeue Pointer command. This will be
+ *     the common case, when drivers timeout on the last submitted request
+ *     and attempt to cancel.
+ *
+ *  2) If the controller is in the middle of a different TD, we turn the TRBs
+ *     into a series of 1-TRB transfer no-op TDs. No-ops shouldn't be chained.
+ *     The controller will need to invalidate the any TRBs it has cached after
+ *     the stop endpoint command.
+ *
+ *  3) The TD may have completed by the time the Stop Endpoint Command
+ *     completes, so software needs to handle that case too.
+ *
+ */
+int cdnsp_ep_dequeue(struct cdnsp_ep *pep, struct cdnsp_request *preq)
+{
+	struct cdnsp_device *pdev = pep->pdev;
+	int ret;
+
+	if (GET_EP_CTX_STATE(pep->out_ctx) == EP_STATE_RUNNING) {
+		ret = cdnsp_cmd_stop_ep(pdev, pep);
+		if (ret)
+			return ret;
+	}
+
+	return cdnsp_remove_request(pdev, preq, pep);
+}
+
+static void cdnsp_zero_in_ctx